For a sustainable semantic web, ontology building and maintenance should be made as simple as possible. Semantic Web has proliferated into various dynamic domains. In these domains, the notion of a concept may change over time, or there may be new concepts in the domains, that are not captured in the older ontology. With constantly changing domain knowledge, there is a need for domain experts to keep the ontology updated, with the changes, in the domain. Often, the domain experts are inundated with so much information that it can be extremely difficult to keep up with the pace of domain changes. Even if domain experts keep up with the domain changes, there are increasingly many such dynamic domains being modeled in the form of an ontology, and it is a significant burden on the domain experts to update the ontology in a timely fashion.
As open data efforts like Linked Open Data (LOD) continues at a rapid pace, more domains would be part of LOD. Most importantly, there will be a need to keep this data updated with the continuous domain changes such that the data is representative of the domain of discourse. While a continuous effort has been made to understanding the evolution of ontology, what has not become clear is how to answer a question that is formed during the update of an ontology.